The present invention relates to a tubular burning wick for oil burning apparatus such as an oil stove, which can be manufactured in a simple manner without requiring any stitching work during the production thereof to preserve its tubular form. More particularly, the invention concerns a stitchless tubular burning wick produced from a length of wick cloth having at least a burner part made of non-combustible textile material and an oil suction part made of oil-soakable fiber material. The cloth is looped into a tube by abutting together the opposite ends of the length of wick cloth and bonding the abutment seam firmly along its axial extent using a special binder element.
Various burning wicks for oil burning apparatus such as an oil stove are known, which have a tubular form and are mounted on a cylindrical wick holder and which are raised or lowered for burning or extinguishing respectively, by manipulating a pinion shaft so as to extend or retract the burner part of the burning wick.
Burning wicks having a burner part and an oil suction part or having a burner part, an oil suction part and a stretchable part are known, for example, from Japanese Laid Open Patent Applications Nos. 17038/1976, 44325/1976 and Japanese Laid Open Utility Model Application No. 157535/1977.
In these burning wicks, a stitching operation, namely, a machine stitching operation, is inevitable during the production process.
Thus, in one example of the production of burning wick, a starting wick cloth having a burner part and an oil suction part is knitted into a continuous band on a knitting machine. This band of wick cloth is then cut to predetermined lengths by a cutter, each of which lengths is looped to form a tube by overlapping the opposite cut ends, whereupon the overlapped end portions art stitched together along the junction seam in a zigzag stitching.
In another example of production of burning wick, a tubular cloth for the burner part and a tubular cloth for the oil suction part of the burning wick are knitted separately on a knitting machine and both the tubes thus knitted are then placed in coaxial alignment such that the adjacent peripheral edges of the tubes are joined together, whereupon these edges are stitched together along the joining seam to form an integrated tubular burning wick.
As indicated above, there has been no substitute for the stitching operation in either of the examples mentioned above, either in the axial or circumferential direction along the junction seam, in order to obtain a tubular burning wick. Especially for tubular burning wicks having smaller diameters, the stitching operation requires special efforts due to the necessity of careful handling, in addition to the easily yieldable nature of the cloth, which results in a decrease in productivity. It is also disadvantageous that the junction portion of the wick has low resistance to tension and torsion due to the occurrence of a weak zone therein resulting from the simple zigzag stitching, which occasionally leads to a failure in the movement of the wick in the form of a deformation of the junction portion due to the external forces imparted in various directions after repeated up-and-down operations of the wick. A further disadvantage is that much human time and skill is necessary for stitching such abutment seams.